Process for the manufacture of alkali-metal salts of halogenated amides of aromatic sulphonic acids



Patented Jan. 22, 1929 UNITED STATES PATENT OFF ICE.

HEINRICH GNNZLER, OF ELBERFELD, GERMANY, ASSIGNOR T WINTH IlROP CHEMICAL Y COMPANY, INC, OF NEW YORK, N. Y.

. PROGESS FOR THE MANUFACTURE OF ALKALLMETAL SALTS AMIDES 0F AROMATIC SULPHONIC ACIDS.

H 0 Drawing.

I have discovered that alkali metal salts of the halogenated amides of aromatic sulfonic acids can be manufactured in a technically very advantageous manner bydecomposing toluene sulfonamides or" their salts in concentrated aqueous solutions by means of bleaching powder and at thesame time, or subsequently, causing to interact therewith an alkali metal salt,- which will produce with the calcium of the resulting calcium salt an insoluble or dit-licultly soluble inorganic precipitate. After filtering the resulting reaction mixture, the resulting alkali metal salts of the halogenated sulfonamides crystallize out on cooling completely 'free from calcium and in good yield.

It is remarkable that under the above conditions good yields can be obtained at all, considering the sensitive nature of the prodacts in question, in view of the elevated temperature required for the separation of the alkali metal salts of the -halogenated sulfonamides. I

Contraste'd with .thl known process for the manufacture of the alkali metal salts in question, the new process involving the salting .out the calcium salt solutions with common salt, offers several technical advantages. It is possible to carry out the operatipn in much smaller vessels andthe production of the alkali metal salts free from calcium can be efiected with certainty even without careful and prolonged washing.

41A sodium hypochlorite solution may be used in place of bleaching powder, so as to obtain a stable chrystallizablesodium salt Quite easily and in one operation. The use of sodium hypochlorite in the solid form is impracticable on account of its, high instability.

- The following examples serve to illustrate the invention:

Ewamplc 1.

22.9 parts by weight of bleaching powdercontaining 62.1% of active-chlorine, 34 parts by weight of p.toluol sulfon'amide and, 14,5 parts by weight of calcined sodium carbon ate are stirred with 100 parts by weight of water, in consequence of which the temperature rises by itself to about C. The reaction mixture is then heated to about 60' 70 C., with stirring, and the calcium carbonatejiormed is separated while :strll hot.

Applicatig'n filed October 12,1925, S

OF HALOGEN ATED erial No. 62,195, and in Germany October 18, 1924.

On cooling the clear solution, crystals of sodium p-toloulsulfo-chloro-amide containing 3' molecules of water of crystallization separate out. The yield amounts of 48 parts by "weight of the sodium salt. a

The p-toluol-sulfo chloro-amide has most probably the formula:

22.9 parts by weight of bleaching powder containing 62.1% of active chlorine and 38.2 parts by weight of calcium p-toluolsulfonamide are stirred with 100 parts by weight of water and 76.5 parts of Glaubers salt (Na SO 10H O) are added. The/ reaction product is then worked by weight up exactly as heretofore described: the yield V amounts to 47 parts b weight of the sodium salt of the amide.

Example 3.

1. Process 'for the manufacture of an alp-toluo sulfonic acid chlor0- kali metal salt of a halogenated amide of an aromatic sulfonic acid compound which comprises decomposing an amide of'an aromatic sulfonic acid com ound, in concentrated aqueous solution, y treatment with bleaching powder thereby formin a halogenated calcium salt of the amid e of the aromatic sulfonic acid compound, and causing to react therewith an inorganic alkali metal salt capable of forming with the calcium of said calcium salt a substantially insoluble inorganic compound of calcium to.

the production of the soluble alkali metal salt of said halogenated amide of the aromatic-sulfonic acid compound.

2. Process 'for the' manufacture of an alkali metal salt of a halogenated amide of an aromatic sulfonicaeid, which comprises.v

' with the calcium of said 0 cium salt a stantially insoluble inorganic compound of, calcium to the production of the soluble aldecomposing a salt of anamide of an aromatic sulfonic acid, in concentrated aqueous solution, by treatment with bleaching owder thereby forming a calcium salt 0 the halogenated amide of the aromatic sulfonic acid, and causing to react therewith an inorganic alkali metal salt ca able of forming su kali metal salt of'said. halogenated amide of the aromatic sulfonic acid.

3. Process for the manufacture of an alkali metal salt of a halogenated amide of an,

bleaching powder at 6070 (3., thereby forming a calcium salt of the halogenated amide of pound, or 'c alkali metal salt capable of forming with the calcium of said calcium salt substantially insoluble inorganic compound of calcium to the production of the soluble alkali metal salt of said halogenated amide of the aromatic .sulfonic acid compound, se arating the said insoluble compound of ca cium, cooling the solution, and recovering the so-precipitated alkali metal salt of the halogenated amide of the aromatic sulfonic acid compound.

In testimony whereof I have my hand.

hereunto set HEINRICH GUNZLER.

the-aromatic sulfonic acid com causing to react therewith an m 

